Yes I have done this. Here is a post about it.
having-2-active-pods-with-only-1-pdm
This pod behavior makes sense because the PDM can only communicate with one pod at a time. When you activate a new one, it tells you to deactivate the “current” pod.
But what if that “current” pod is dead or has fallen off and is lost? If you can’t deactivate it, you can “discard” it, meaning the new pod can become the pod that is communicating.
Otherwise if they did not do it this way, if you ever lost a pod you could never activate a new pod because it would make you deactivate the old pod first, and if it was lost, you could never deactivate it.
And the idea of having a pod continue to run even if your PDM is not around also makes sense, because that lets you go to the store without your PDM, or swim or take a shower, and your basal can continue no matter where the PDM is.
Does all that make sense?